1. Field of the Invention
The present invention relates to a hermetic compressor, and more particularly to an improved stator stopper structure for a hermetic compressor, capable of preventing stator stoppers from undesirably crooking as well as preventing a noise occurrence resulting from an external impact which may occur when support springs hit onto the stator stoppers in a handling or transportation of the hermetic compressor.
2. Description of the Background Art
As shown in FIG. 1, a general hermetic compressor includes: a hermetically sealed container 1; a frame 2 provided inside the container 1; and a motor unit disposed below the frame 2 and including a stator 3 and a rotor 4.
Onto respective spring seats 11 disposed on corresponding lower portions in the hermetic compressor, there are fittingly provided corresponding support springs 12 which serve to support the stator 3.
A crank shaft 5 having an eccentric portion 5a disposed at an upper end thereof is fitted into the rotor 4. A cylinder 6 is connected to an upper portion of the frame 2.
A piston 8 is engaged to the eccentric portion 5a of the crank shaft 5 and horizontally reciprocates in the cylinder 6.
A valve plate 8 is attached onto an end portion of the cylinder 6, and a head cover 9 is attached onto a side portion of the valve plate 8. A suction muffler (not shown) is mounted on a portion of the head cover 9.
With reference to FIG. 1, the operation of the conventional hermetic compressor will now be described.
First, when power is applied to the motor of the hermetic compressor, the rotor 4 begins its rotation, thereby rotating the crank shaft 5 fitted into the rotor 4. Accordingly, the piston 7 connected to the eccentric portion 5a of the crank shaft 5 reciprocates in the cylinder 6.
With the piston 7 making its reciprocating movement, a low-temperature low-pressure refrigerant gas is drawn through a suction port (not shown) formed in a side portion of the head cover 9 into the cylinder 6. The intaken refrigerant gas is compressed into a high-temperature high-pressure refrigerant gas in the cylinder 6, and exhausted through an exhaust port (not shown) formed in another side portion of the head cover 9.
Referring to FIGS. 1 and 2, there will be now explained a stator stopper structure of the hermetic compressor, wherein a vibration caused by a rotation of the crank shaft 5 or by the refrigerant gas compression may be absorbed in the compressor.
Initially, a square type stator 3 includes a central opening 3b through which the rotor 4 is provided and makes its rotation therein. A pair of stator stoppers 10 are fixed by bolts 3a onto a lower end of the stator 3.
Spring supports 13a, 13b are downwardly extended from the lower surface of the stator stoppers 10.
Spring seats 11 corresponding to the spring supports 13a, 13b extended from the stator stoppers 10 are formed on predetermined portions of the bottom surface of a casing of the hermetic compressor.
Here, the stator stopper structure for absorbing vibration in the compressor includes a mechanism in which the support springs 12 are respectively disposed between the corresponding stator stoppers 10 mounted on the lower surface of the stator 3 and the corresponding spring seats 11 mounted on bottom portions in the hermetic compressor.
With regard to the stator stoppers 10 in the conventional hermetic compressor, the right side and left side spring supports 13a, 13b are not symmetrical with respect to an axis of the crank shaft 5. Instead, the left side spring supports 13b are disposed outwardly farther from the axis of the crank shaft 5 than the right side spring supports 13a.
Also, because respective dimensions D between the stator stoppers 10 and the spring seats 11 are identical, a vertical impact that may occur during a handling or transportation of the compressor may be applied to each side of the stator stoppers 10 in the form of an identical force F.
However, when such a force F is identically applied to each of the spring supports 13a, 13b extended from the stator stoppers 10, as shown in FIG. 3, a bending momentum inflicted on the stator stoppers 10 may become increased. Here, the spring supports 13b are extended from the stator stoppers 10 and are spaced farther from the axis of the crank shaft 5, compared to the stator stoppers 10 from which the spring supports 13a are extended, thereby causing each left portion of the stator stoppers to disadvantageously crook.
As a result, the thusly crooked stator stoppers 10 tend to cause an obstruction with regard to the support springs 12 while undergoing a compress in correspondence to the rotation of the crank shaft 5 in the hermetic compressor, thereby resulting in an undesirable noise or in worse case even causing the springs 12 to escape from the spring supports 13b.